A5090865253- Topological Materials and Phenomena
- Quantum and electron transport phenomena
- Physics of Superconductivity and Magnetism
- Iron-based superconductors research
- Advanced Condensed Matter Physics
- Rare-earth and actinide compounds
- Quantum many-body systems
- Graphene research and applications
- Photonic and Optical Devices
- Semiconductor Quantum Structures and Devices
- Plasmonic and Surface Plasmon Research
- Superconductivity in MgB2 and Alloys
- Surface and Thin Film Phenomena
- Magnetic properties of thin films
- Quantum, superfluid, helium dynamics
- Metallurgy and Material Science
- Quantum Dots Synthesis And Properties
- Cold Atom Physics and Bose-Einstein Condensates
- Magnetic Properties and Applications
- Electronic and Structural Properties of Oxides
- Mechanical and Optical Resonators
- Quantum Mechanics and Non-Hermitian Physics
- ZnO doping and properties
- 2D Materials and Applications
- Chalcogenide Semiconductor Thin Films
University of Houston
2024-2025
University of California, Berkeley
2022-2025
Massachusetts Institute of Technology
2018-2021
University of Warsaw
2012-2018
Inter Metal (Poland)
2018
University of Waterloo
2015
Majorana zero-modes (MZMs) are spatially-localized zero-energy fractional quasiparticles with non-Abelian braiding statistics that hold a great promise for topological quantum computing. Due to its particle-antiparticle equivalence, an MZM exhibits robust resonant Andreev reflection and 2e2/h quantized conductance at low temperature. By utilizing variable-tunnel-coupled scanning tunneling spectroscopy, we study of vortex bound states on FeTe0.55Se0.45 superconductors. We report observations...
Altermagnets are a new class of magnetic materials, which exhibit large spin splitting, but due to the combined and real space group symmetry protection maintain zero net macroscopic magnetization. Such characteristic may prove them be superior in applications superconducting heterostructures thus here we investigate Andreev reflection at altermagnet/superconductor interface. We compare contrast altermagnets other revealing qualitative differences behavior altermagnetic junction depending on...
Solotronics, optoelectronics based on solitary dopants, is an emerging field of research and technology reaching the ultimate limit miniaturization. It aims at exploiting quantum properties individual ions or defects embedded in a semiconductor matrix. As already shown, optical control spin magnetic ion feasible employing photo-generated carriers confined dot. A non-radiative recombination, regarded as severe problem, limited development dots with ions. Our photoluminescence studies on, so...
We show that Dirac fermion systems in two dimensions generally exhibit disorder-induced nodal arc replacing the point and tilted cone, provided components of correspond to distinct orbitals unrelated by symmetry. This result is explicitly demonstrated using renormalization group analysis a disordered model we introduce, where disorder potential acts differently on orbitals. As numerical simulations self-consistent Born approximation calculation, this drives system into new strongly phase.
Iron-chalcogenide superconductors have emerged as a promising Majorana platform for topological quantum computation. By combining band and superconductivity in single material, they provide significant advantage to realize isolated zero modes. However, iron-chalcogenide superconductors, especially Fe(Te,Se), suffer from strong inhomogeneity which may hamper their practical application. In addition, some iron-pnictide been demonstrated surface states, yet no mode has observed inside vortices,...
Since the early days of Bardeen-Cooper-Schrieffer theory, it has been predicted that a sufficiently large supercurrent can close energy gap in superconductor and creates gapless Bogoliubov quasiparticles through Doppler shift quasiparticle due to Cooper pair momentum. In this superconducting state, zero-energy reside on segment normal state Fermi surface, while its remaining part is still gapped. The finite density states field-induced quasiparticles, known as Volovik effect, observed...
A new type of linear-response Hall effect is a quantum analog to the Magnus effect, and has implications for current rectification devices provides tool map Berry curvature distribution in momentum space.
We analyze the thermoelectric response of Dirac and Weyl semimetals using semiclassical approach, focusing on extrinsic contributions due to skew-scattering side jump. Our results apply linear Nernst effect in ferromagnetic materials such as ${\mathrm{Fe}}_{3}{\mathrm{Sn}}_{2}$ like ${\mathrm{Co}}_{3}{\mathrm{Sn}}_{2}{\mathrm{S}}_{2}$. In case we obtain a very good agreement with known experimental anomalous Hall measurements, based that predict large this material. also extend investigation...
While optical techniques are fundamental in the investigation of superconducting state, many clean superconductors combination particle-hole and inversion symmetries prevents momentum-conserving transitions. Here, authors show that by driving supercurrent through sample transitions across gap become allowed even single-band systems. As signal depends strongly on pairing as well underlying normal supercurrent-driven conductivity provides a new way determining state properties.
Understanding the nature of strongly correlated states in flat-band materials (such as moiré heterostructures) is at forefront both experimental and theoretical pursuits. While magnetotransport, scanning probe, optical techniques are often very successful investigating properties underlying order, exact ground state remains unknown. Here, we propose to leverage strong light-matter coupling present systems gain insight through dynamical dielectric response into structure many-body state. We...
We propose a new current-driven mechanism for achieving significant plasmon dispersion nonreciprocity in systems with narrow, strongly hybridized electron bands. The magnitude of the effect is controlled by strength electron-electron interactions α, which leads to its particular prominence moiré materials, characterized α≫1. Moreover, this phenomenon most evident regime where Landau damping quenched and lifetime increased. synergy these two effects holds great promise novel optoelectronic...
Abstract The iron-based superconductor is emerging as a promising platform for Majorana zero mode, which can be used to implement topological quantum computation. One of the most significant advances this appearance large vortex level spacing that strongly protects mode from other low-lying quasiparticles. Despite advantages in context physics research, inhomogeneity various aspects hampers practical construction qubits compounds studied so far. Here we show stoichiometric LiFeAs good...
Gapless helical edge modes are a hallmark of the quantum spin Hall effect. Protected by time-reversal symmetry, each contributes quantized zero-temperature conductance ${G}_{0}\ensuremath{\equiv}{e}^{2}/h$. However, experimentally observed in ${\mathrm{WTe}}_{2}$ decreases below ${G}_{0}$ per already at lengths around 100 nm, even absence explicit breaking due to an external field or magnetic impurities. In this work, we show how excitonic condensate with spin-spiral order that can form...
We study multiterminal Majorana and conventional superconducting islands in the vicinity of charge degeneracy point using bosonization numerical renormalization group. Both models map to multichannel Kondo problem, but for noninteracting normal leads they flow different non-Fermi liquid fixed points at low temperatures. compare contrast both cases by numerically obtaining full crossover temperature regime predict distinctive transport signatures. attribute differences between types a crucial...
When Co$^{2+}$ impurity is embedded in semiconductor structure, crystal strain strongly influences zero-filed splitting between states with spin projection $S_z = \pm 3/2$ and 1/2$. Experimental evidences of this effect have been given previous studies, however direct measurement the induced zero-field has inaccessible so far. Here determined thanks to magneto-optical studies individual ion epitaxial CdTe quantum dot ZnTe barrier. Using partially allowed optical transitions we measure...
We study quantum point contacts in two-dimensional topological insulators by means of transport simulations for InAs/GaSb heterostructures and HgTe/(Hg,Cd)Te wells. In InAs/GaSb, the density edge states shows an oscillatory decay as a function distance to edge. This is contrast behavior HgTe wells, which into bulk simple exponential manner. The difference between two materials brought about spatial separation electrons holes affects magnitudes parameters describing particle-hole asymmetry...
We report on epitaxial growth of diluted magnetic semiconductor (Zn,Co)Te.Reectivity spectra reveal excitonic transition which split under eld due to giant Zeeman eect.Magnetooptical eects can be described using literature data.
We present a fabrication process for graphene-based devices where graphene monolayer is suspended above local metallic gate placed in trench. As an example we detail the steps of field-effect transistor. The are built on bare high-resistivity silicon substrate. At temperatures 77~K and below, observe modulation resistivity by voltage applied to gate. This approach enables new experiments involving superconducting qubits nano-electromechanical resonators. method applicable other...
Abstract Majorana bound states provide a fertile ground for both investigation of fundamental phenomena as well applications in quantum computation. However, despite enormous experimental and theoretical efforts, the currently available platforms suffer from multitude issues that prevent full realization their potential. Therefore, improved systems are still highly sought after. Here we present platform creating 2D gapless superconducting state spin-helical under in-plane magnetic or Zeeman...